Joe Salerno, a well driller excavating geological samples for a university project in the small Florida town of Montverde, is contaminated by a strange liquid that transposes his senses of pain and pleasure. Unaware he has been infected with a dangerous virus, he tries to impress Maria, a pretty waitress at the local diner, who is romantically involved with Allen Greenfield.

Allen's out-of-town job is affecting his relationship with Maria, so he decides to quit and propose to her. Whe he arrives in Montverde, he finds significant changes there. Maria, who earlier at hinted at marriage, now seems indifferent to it. The town is practically uninhabited and has a much darker air about it, and tattoo parlors and seedy shops have replaced the nice stores that once lined the main street. When Allen begins to investigate, he discovers the dreadful virus has forced the town people into self-mutilation.